1. Field of the Invention
The present invention relates to a corneal surgery apparatus for correcting a refractive error by ablating corneal tissue with a laser beam and methods of determining data concerning the correction.
2. Description of Related Art
Refractive errors of an eye include myopia, astigmatism, hyperopia, and presbyopia which makes it difficult to see things from near with aging. Conventionally, correction of presbyopia has been conducted with eyeglasses, but contact lenses have also been used in recent years. On the other hand, refractive corrections of myopia, astigmatism and hyperopia have been conducted with a corneal surgery apparatus for changing a corneal shape with a laser beam as well as with eyeglasses and contact lenses. In the correction of presbyopia, however, patterns of the correction vary in accordance with patients' life styles. In corrective surgery with a laser beam, this variance makes it difficult to correct presbyopia according to an optimum pattern of correction desired by a patient. In addition, corrective surgery using a laser beam has a problem in that it is irreversible unlike the correction with eyeglasses or contact lenses.